public class myprogram {
    public static void main(String[] args) {
        double a=1.0;
        System.out.println(a);

        int c=1;
        int b=2;
        System.out.println(c/b);//0

        double m = 1.0;
        double n = 2.0;
        System.out.println(m / n);
        // 执行结果0.5

        double num = 1.1;
        System.out.println(num * num);
        // 执行结果1.2100000000000002
    }
}
